A Do Not Resuscitate, or DNR orer is a written order from a doctor that resuscitation should not be attempted if a person suffers cardiac or respiratory arrest. Such an order may be instituted on the basis of an advance directive from a person, or from someone entitled to make decisions on their behalf, such as a health care proxy; in some jurisdictions, such orders can also be instituted on the basis of a physician's own initiative, usually when resuscitation would not alter the ultimate outcome of a disease, and is designed to prevent unnecessary suffering.